Triangle Big muff Pi power problem....

[killerkev]

So, I  bought a old triangle BMP to see what the fuss about. The pedal worked when I bought it. After realizing the pots where not original ( as I posted before) and had way to much wire all over the place, I shortened the wiring and soldered the posts to the board like they should be.  After that I changed it to true bypass with a 3PDT switch (I've done this a hundred times in the past with other BMP pedals).

So here is the deal, when the power lead to the circuit board is removed, the voltage from the battery is the same until I solder it to the correct position on the board. the voltage drops to practicaly zero, When I disconnect the battery, the voltage reads lower and after a few minutes reads like it did before. The pedal does not work now. Trannies are FS 36999. I do not believe they are PNP because the same trannies are in a Ram's head I have which are negative grounded NPN. Nothing else was changed. Like I said it worked before I screwed with the pots but I just shorted the wiring to the board and pots. Maybe fixed some bridges close to the pots that were already there before. Any suggestions are welcomed!

[R.G.]

Like I said it worked before I screwed with the pots but I just shorted the wiring to the board and pots. Maybe fixed some bridges close to the pots that were already there before. Any suggestions are welcomed!

Like Sherlock Holmes said "Eliminate the impossible, Watson, and what remains must be the truth."

If it worked before you changed the wires, and didn't afterwards, something you did about re-hooking the wires or maybe fixing some bridges close to the pots made it not work.

How is it similar and/or different from the hundred other BMPs you've worked on?

[killerkev]

Well, As I said it the first triangle circuit board I've had in my hands.  I thought it was pretty odd that it didn;t work after I shorted these pot leads. I will have to triple check the pinout for these pots. I didn't think that even wiring the pots incorrectly would result in such a drain from the power source. RG your the man, tell me what you think. I will do continuity checks on every path and see what I come up with. What would cause such a drain though?

[the dude]

there is short somewhere in the circuit, probaly 9 volt rail to ground. Inspect the 9 volt rail eveywhere and check to see if it is short to ground. Use your ohm setting and see if there is continunity to ground.

[killerkev]

Thanks Dude! It appears that there was a thin little bridge connecting to ground. This has also enlighted me to some issues I'm having on a trailer. Hope to plug it in tonight.